Description Of Business And Basis Of Presentation [Line Items]

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- Definition

Revenue From Contract With Customers, Number Of Primary Markets

+ References

No definition available.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	12 Months Ended
	Sep. 27, 2019 segment market	Sep. 28, 2018 USD ($)	Sep. 28, 2019 USD ($)
Description Of Business And Basis Of Presentation [Line Items]
Number of reportable operating segments \| segment	1
Number of primary markets \| market	3
Minimum
Description Of Business And Basis Of Presentation [Line Items]
Definite-lived intangible asset useful life	5 years
Maximum
Description Of Business And Basis Of Presentation [Line Items]
Definite-lived intangible asset useful life	14 years
Disposal Group, Not Discontinued Operations \| LR4
Description Of Business And Basis Of Presentation [Line Items]
Gain (loss) on disposal		$ 34.3
Scenario, Forecast \| Accounting Standards Update 2016-02 \| Minimum
Description Of Business And Basis Of Presentation [Line Items]
Operating lease liability			$ 42.0
Operating lease right of use asset			33.0
Scenario, Forecast \| Accounting Standards Update 2016-02 \| Maximum
Description Of Business And Basis Of Presentation [Line Items]
Operating lease liability			46.0
Operating lease right of use asset			$ 37.0